模拟胃肠道消化液中小球藻类金属硫蛋白对镉离子的结合作用研究

利用锌诱导小球藻,通过提取分离和纯化,获得锌结合类金属硫蛋白(MT-like蛋白)。通过透析过程,研究模拟胃、肠道消化液中MT-like蛋白对Cd²⁺的结合作用。结果表明,在模拟胃液中MT-like蛋白处于脱金属状态,与Cd²⁺的结合能力弱。而在肠消化液中,MT-like蛋白能与Cd²⁺结合,20 mg·L^-1 MT-like蛋白与100μg·L^-1 Cd²⁺的结合率可达46.0%。研究发现,在模拟胃、肠液中胃蛋白酶和胰蛋白酶都会降低MT-like蛋白对Cd^2+的结合能力。研究结果对进一步开发MT-like蛋白作为Cd²⁺的生物解毒剂具有重要意义。

Binding effect of MT-like proteins from Chlorella sp .to Cd2+ in simulate gastrointestinal digestive juices

The analogues of metallothionein(MT)was produced from Chlorella sp .by Zn²⁺ inducement.After extraction and purification,the metallothionein-like proteins(MT-like proteins)was obtained.In addition,the binding effect of MT-like proteins to cadmium ions(Cd²⁺ )in simulate gastrointestinal digestive juices was carried out through dialysis.The results showed that weak binding ability was observed in simulate gastric juice because the MT-like proteins were in demetalization state at low pH.But the binding ability was strong in simulate intestinal fluid with the binding rate of 46.0%for 20 mg·L^-1 of MT-like to 100 μg·L^-1 of Cd²⁺ .The results also found that both pepsin and trypsin in gastrointestinal fluids might reduce the binding rates of MT-like proteins to Cd²⁺ .The results laid a foundation for the further development of MT-like proteins as biological detoxicant reagents for heavy metals.